phi=linspace(0,2*pi,1000);
ac=acos(cos(phi))*180/pi;
as=asin(sin(phi))*180/pi;
phi=phi*180/pi;
aco=[phi',ac'];
asi=[phi',as'];

plot(phi,ac,'k');
hold on;
plot(phi,as,'r--');
title('Arkusfunktionen');
xlabel('\phi');
ylabel('\phi_{berechnet}');
legend('arccos(cos(\phi))','arcsin(sin(\phi))');